The answer is e, as in terms of d, proteins are not sandwiched between the two bilayers, but wedged in the bilayer to selectively let in different molecules. With c, phospholipids do not drift, into the membrane, for it is the membrane itself. With b it is the other way around, the phospholipid bilayer makes up the membrane, and proteins are embedded into it. Lastly, for a, a fluid mosaic model wouldn’t portray phospholipids drifting in the dark phospholipid bilayer, as they are an independent molecule consisting only as the cell membrane. Hope that’s helpful! :)
The exons of the pre -mRNA contain the protein -coding regions.
Pre mRNA is the first made mRNA transcript and requires undergo many post transcriptional modifications for the formation of a mature mRNA.
The exons are the regions of the pre-mRNA that are found in the mature RNA, after the splicing of introns takes place.
RNA splicing is the process in which the non-coding segments of the RNA, which are known as introns, are removed by the help of small nuclear ribonucleoproteins. These SnRNPs make the spliceosome, which catalyzes the process of splicing.
After the introns are removed by the splicing process, the exons are covalently joined, which forms the mature mRNA.
Learn more about mRNA from here:
brainly.com/question/21312423
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